Antimicrobial Agents Flashcards
What does the Gram staining relies on to differentiate bacteria?
a. Difference in the plasma membrane
b. Difference in the cell wall
c. Difference in the ribosomes
d. Difference in the genetic cod
b. Difference in the cell wall
What is meant by spectrum of action?
a. It indicates the class of antibacterial an agent belongs to
b. It indicates the diseases an antibacterial agent can treat
c. It indicates the strength of an antibacterial agent
d. It indicates the type of bacteria that are susceptible to an antibacterial agents
d. It indicates the type of bacteria that are susceptible to an antibacterial agents
Which of the following statements about classes of antibacterial is incorrect
a. Antibacterial agent belonging to the same class share the same mechanism of action
b. Antibacterial agents of different classes have different molecular structure
c. Antibacterial agents of different classes always target different structures in the bacterial cell
d. Antibacterial agents of the same class may show cross-resistance
c. Antibacterial agents of different classes always target different structures in the bacterial cell
Which is the mechanism of action of beta lactams?
a. Inhibition of RNA synthesis
b. Inhibition of cell wall synthesis
c. Inhibition of protein synthesis
d. Inhibition of DNA replication
b. Inhibition of cell wall synthesis
Which statement about penicillins mechanism of action is incorrect?
a. Penicillins are active only against Gram positive bacteria
b. The beta lactam ring opens when penicillin interacts with the target enzyme
c. Penicillins bind covalently with the active site of the enzyme
d. Penicillins, cephalosporins, monobactams and carbapenems share the same mechanism of action
a. Penicillins are active only against Gram positive bacteria
What is beta lactamase?
a. An enzyme found in fungi that synthesise beta lactams
b. An agent that is administered with beta lactam to circumvent resistance
c. The bacterial enzyme responsible for beta lactams resistance
d. The enzyme responsible for allergy to beta lactams
c. The bacterial enzyme responsible for beta lactams resistance
Which antibacterial agent does NOT inhibit cell wall synthesis?
a. Cycloserin
b. Vancomycin
c. Chloramphenicol
d. Cephalosporin
e. Bacitracin
c. Chloramphenicol
How can we define an antibacterial agent that prevents the replication and/or growth of bacteria but relies on the immune system of the patient to eradicate the infection completely?
a. A bacteriostatic agent
b. A bactericidal agent
a. A bacteriostatic agent
Why is bacitracin recommended for the treatment of topical infection?
a. Because it is not stable in solution and poorly absorbed
b. Because of systemic toxicity
c. Because of its wide spectrum
d. Because it induces resistance quickly
a. Because it is not stable in solution and poorly absorbed
What do aminoglycosides, macrolides, tetracyclines and oxazolidinones have in common?
a. They do not induce resistance
b. They are all bacteriostatic
c. They have similar molecular structure
d. They all inhibit protein synthesis in bacteria
d. They all inhibit protein synthesis in bacteria
Which of the following classes of antibacterial agents is obtained by chemical synthesis?
a. Macrolides
b. Oxazolidinones
c. Chloramphenicol
d. Aminoglycosides
e. Tetracyclines
b. Oxazolidinones
Which organelle is targeted by antibacterial agents that inhibit protein synthesis?
a. The cell wall
b. The plasmid
c. The mitochondrion
d. The ribosome
d. The ribosome
Which of the following agents is toxic for newborns?
a. Erythromycin
b. Chloramphenicol
c. Doxacyclin
d. Streptomycin
b. Chloramphenicol
What is the mechanism of action of quinolones?
a. Quinolones form radicals causing damage to bacterial DNA
b. Quinolones bind to bacterial DNA preventing its replication
c. Quinolones bind to the 30s subunit of the ribosome preventing the attachment of tRNA
d. Quinolones bind to DNA gyrase and topoisomerase preventing the coiling of the bacterial DNA
d. Quinolones bind to DNA gyrase and topoisomerase preventing the coiling of the bacterial DNA
